1980, David Guy Compton, The Unsleeping Eye, p. 130:
See you next Tuesday — it's a dirty insult. The initials make a dirty insult.
1997, Philip Thody, Don't Do It!: A Dictionary of the Forbidden, p. 143:
In the Guardian for 2 November 1989, Katie Campbell mentioned the disparaging See You Next Tuesday as a description for an unreliable young man (= ****), and commented: 'Imagine a word so powerful that it has to be disguised, even when used as a term of abuse.'
2005, Kevin Weisman, Alias Assumed: Sex, Lies and SD-6, p. 13:
"See you next Tuesday," she said crisply, the camera holding her in close-up an extra beat for emphasis. You could almost hear the thud of knowing viewers falling off their chairs. In decades-old high-school vernacular, "See you next Tuesday" is code for the word that starts with the letters "c-u," means female genitalia and is used to insult a woman when "bitch" just isn't strong enough.
2006, Nick Hemsley, Clock, p. 96:
'See you next Tuesday.' I learnt that at my convent school (My mother was Catholic). We would say it to the nuns who didn't have a clue what it meant...
2006, Jane May, Doggy Style, p. 243:
"That diva may be gorgeous, but she's a real, well, you know, a see-you-next-Tuesday." "A what?" asked Jen. I cocked my head. Curious, myself. "She's—pardon the expression—a ****."
Etymology
Derived from the fact that "see" and "you" are homophones for "c" and "u", while the first letters of "next" and "Tuesday" are "n" and "t".